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Article

Keywords:
connected; H-closed; extensions; condensations
Summary:
A non-connected, Hausdorff space with a countable network has a connected Hausdorff-subtopology iff the space is not-H-closed. This result answers two questions posed by Tkačenko, Tkachuk, Uspenskij, and Wilson [Comment. Math. Univ. Carolinae 37 (1996), 825--841]. A non-H-closed, Hausdorff space with countable $\pi $-weight and no connected, Hausdorff subtopology is provided.
References:
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[PW2] Porter J.R., Woods R.G.: Subspaces of connected spaces. Topology Appl. 68 (1996), 113-131. MR 1374077 | Zbl 0855.54025
[V] Vermeer J.: Private communication, 1984.
[TTUW] Tkačenko M.G., Tkachuk V.V., Uspenskij V.V., Wilson R.G.: In quest of weaker connected topologies. Comment. Math Univ. Carolinae 37.4 (1996), 825-841. MR 1440714
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